Automated dialing systems are often used to place telephone calls and then connect the called party to a resource only after the called party has answered the telephone. An advantage of using an automated dialing system is that the resource is not expended manually dialing the call and waiting for the called party to answer the telephone. Further, if the line is busy or the called party does not answer the telephone after a predetermined number of rings—no resource time is expended on the unanswered call.
One problem with automated dialing systems is that if an answering machine answers the call, the resource may be connected to the answering machine rather than the called party.
To alleviate this problem, several systems have been developed for detecting whether a call has been answered by an answering machine or a person. For example, U.S. Pat. No. 5,371,787 to Hamilton uses a combination of a click detector, a ring detector, a voice detector, click analyzer, ring analyzer, noise analyzer, answer analyzer, silence analyzer, and voice analyzer to distinguish whether a telephone was answered by an answering machine based on time intervals of voice and silence within the audio signal.
Each of U.S. Pat. No. 5,430,792 to Jesurum et al., U.S. Pat. No. 5,724,420 to Torgrim, and U.S. Pat. No. 5,828,731 to Szlam et al. similarly distinguishes between the existence of voice and silence within the audio signal to determine whether the telephone has been answered by an answering machine.
In a separate field of technology, traditional ring back (e.g. a cadence of 2 seconds on, 4 seconds off in the US) is being replaced by customized ring back audio content. For example, the audio content can be any recorded audio such as a spoken message, music, a performed audio monolog (such as comedy), or other recorded audible sound.
A problem exists in that the known technology for distinguishing between whether a telephone has been answered by a machine or a person uses detecting the presence of (or detecting of the discontinuity of) transitions in the audio signal between: i) “ring” and “silence” in traditional ring back cadence, ii) clicks, iii) voice, and iv) silence to both distinguish when a telephone is answered and whether the telephone was answered by a person or a machine.
Replacing the traditional ring back cadence with audio content eliminates an easily detectible sequence of events within the audio signal (the transitions between ring and silence) that is used by traditional systems to: i) detect answering of the telephone; and ii) initiate the measurement of time elapsing between the audio discontinuities of voice and silence used as input for the algorithms for determining whether the call was answered by a person or an answering machine.
In one aspect of the present invention, what is needed is a system and method for distinguishing audio signals received in response to placing an outbound call and, more particularly, to an automated system and method for analyzing audio content (as opposed to discontinuities in the audio signal) and taking one of a plurality of actions based on a characteristic or set of characteristics of the audio signal.
In another aspect of the present invention, what is needed is a system and method for detecting when an outbound telephone call has been answered in response to placing an outbound call that does not rely on detecting traditional ring back cadence.
In yet another aspect of the present invention, what is needed is a system and method for detecting whether an outbound telephone call has been answered in a network lacking traditional ring back cadence and, if answered, whether such outbound call has been answered by a person or an answering machine.